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Posted on 27 November 2010 by dana1981

A common argument against investing in renewable energy technology is that it cannot provide baseload power - that is, the ability to provide energy at all times on all days. This raises two questions - (i) are there renewable energy sources that can provide baseload power, and (ii) do we even need renewable baseload energy?

Does Renewable Energy Need to Provide Baseload Power?

A common myth is that because some types of renewable energy do not provide baseload power, they require an equivalent amount of backup power provided by fossil fuel plants. However, this is simply untrue. As wind production fluctuates, it can be supplemented if necessary by a form of baseload power which can start up or whose output can be changed in a relatively short period of time. Hydroelectric and natural gas plants are common choices for this type of reserve power (AWEA 2008). Although a fossil fuel, combustion of natural gas emits only 45% as much carbon dioxide as combustion of coal, and hydroelectric is of course a very low-carbon energy source.

The current energy production structure consists primarily of coal and nuclear energy providing baseload power, while natural gas and hydroelectric power generally provide the variable reserves to meet peak demand. Coal is cheap, dirty, and the plant output cannot be varied easily. It also has high initial investment cost and a long return on investment time. Hydroelectric power is also cheap, clean, and good for both baseload and meeting peak demand, but limited by available natural sources. Natural gas is less dirty than coal, more expensive and used for peak demand. Nuclear power is a low-carbon power source, but with an extremely high investment cost and long return on investment time.

Renewable energy can be used to replace some higher-carbon sources of energy in the power grid and achieve a reduction in total greenhouse gas emissions from power generation, even if not used to provide baseload power. Intermittent renewables can provide 10-20% of our electricity, with hydroelectric and other baseload renewable sources (see below) on top of that. Even if the rapid growth in wind and other intermittent renewable sources continues, it will be over a decade before storage of the intermittent sources becomes a necessity.

Renewable Baseload Energy Sources

Of course in an ideal world, renewable sources would meet all of our energy needs. And there are several means by which renewable energy can indeed provide baseload power.

Concentrated Solar Thermal

One of the more promising renewable energy technologies is concentrated solar thermal, which uses a system of mirrors or lenses to focus solar radiation on a collector. This type of system can collect and store energy in pressurized steam, molten salt, phase change materials, or purified graphite.

The first test of a large-scale thermal solar power tower plant was Solar One in the California Mojave Desert, constructed in 1981. The project produced 10 megawatts (MW) of electricity using 1,818 mirrors, concentrating solar radiation onto a tower which used high-temperature heat transfer fluid to carry the energy to a boiler on the ground, where the steam was used to spin a series of turbines. Water was used as an energy storage medium for Solar One. The system was redesigned in 1995 and renamed Solar Two, which used molten salt as an energy storage medium. In this type of system, molten salt at 290ºC is pumped from a cold storage tank through the receiver where it is heated to about 565ºC. The heated salt then moves on to the hot storage tank (Figure 1). When power is needed from the plant, the hot salt is pumped to a generator that produces steam, which activates a turbine/generator system that creates electricity (NREL 2001).

The Solar Two molten salt system was capable of storing enough energy to produce power three hours after the Sun had set. By using thermal storage, power tower plants can potentially operate for 65 percent of the year without the need for a back-up fuel source. The first commercial concentrated solar thermal plant with molten salt storage - Andasol 1 - was completed in Spain in 2009. Andasol 1 produces 50 MW of power and the molten salt storage can continue to power the plant for approximately 7.5 hours.

Abengoa Solar is building a 280 MW solar thermal plant in Arizona (the Solana Generating Station), scheduled to begin operation in 2013. This plant will also have a molten salt system with up to 6 hours worth of storage. The electrical utility Arizona Public Service has contracted to purchase the power from Solana station for approximately 14 cents per kilawatt-hour.

Italian utility Enel recently unveiled "Archimede", the first concentrated solar thermal plant to use molten salts for both heat storage and heat transfer. Molten salts can operate at higher temperatures than oils, which gives Archimede higher efficiency and power output. With the higher temperature heat storage allowed by the direct use of salts, Archimede can extend its operating hours further than an oil-operated solar thermal plant with molten salt storage. Archimede is a 5 MW plant with 8 hours of storage capacity.

The National Renewable Energy Laboratory provides a long list of concentrated solar thermal plants in operation, under construction, and in development, many of which have energy storage systems. In short, solar thermal molten salt power storage is already a reality, and a growing resource.

Geothermal

Geothermal systems extract energy from water exposed to hot rock deep beneath the earth's surface, and thus do not face the intermittency problems of other renewable energy sources like wind and solar. An expert panel concluded that geothermal sources could produce approximately 100 gigawatts (GW) of baseload power to the USA by mid-century, which is approximately 10% of current US generating capacity (MIT 2006). The panel also concluded that a research and development investment of less than $1 billion would make geothermal energy economically viable.

The MIT-led report focuses on a technology called enhanced or engineered geothermal systems (EGS), which doesn't require ideal subsurface conditions and could theoretically work anywhere. installing an EGS plant typically involves drilling a 10- to 12-inch-wide, three- to four-kilometer-deep hole, expanding existing fractures in the rock at the bottom of the hole by pumping down water under high pressure, and drilling a second hole into those fractures. Water pumped down one hole courses through the gaps in the rock, heats up, and flows back to the surface through the second hole. Finally, a plant harvests the heat and circulates the cooled water back down into the cracks (MIT 2007).

Currently there are 10.7 GW of geothermal power online globally, with a 20% increase in geothermal power online capacity since 2005. The USA leads the world in geothermal production with 3.1 GW of installed capacity from 77 power plants (GEA 2010).

Wind Compressed Air Energy Storage (CAES)

Various methods of storing wind energy have been explored, including pumped hydroelectric storage, batteries, superconducting magnets, flywheels, regenerative fuel cells, and CAES. CAES has been identified as the most promising technology for utility-scale bulk wind energy storage due to relatively low costs, environmental impacts, and high reliability (Cavallo 2005). CAES plants are currently operational in Huntorf, Germany (290 MW, since 1978) and Macintosh, Alabama (110 MW, since 1991). Recently this type of system has been considered to solve the intermittency difficulties associated with wind turbines. It is estimated that more than 80% of the U.S. territory has geology suitable for such underground storage (Gardner and Haynes 2007).

The Iowa Stored Energy Park has been proposed to store air in an underground geologic structure during time periods of low customer electric demand and high wind. The project is hoping to store a 20 week supply of compressed air and have approximately 270 MW of generating capacity. The project is anticipated to be operational in 2015.

A similar system has been proposed to create a wind turbine-air compressor. Instead of generating electricity, each wind turbine will pump air into CAES. This approach has the potential for saving money and improving overall efficiency by eliminating the intermediate and unnecessary electrical generation between the turbine and the air compressor (Gardner and Haynes 2007).

Pumped Heat Energy Storage

Another promising energy storage technology involves pumping heat between tanks containing hot and cold insulated gravel. Electrical power is input to the system, which compresses/expands air to approximately 500°C on the hot side and -150°C on the cold side. The air is passed through the two piles of gravel where it gives up its heat/cold to the gravel. In order to regenerate the electricity, the cycle is simply reversed. The benefits of this type of system are that it would take up relatively little space, the round-trip efficiency is approximately 75%, and gravel is a very cheap and abundant material.

Spent Electric Vehicle (EV) Battery Storage

As plug-in hybrids and electric vehicles become more commonplace, the possibility exists to utilize the spent EV batteries for power grid storage after their automotive life, at which point they will still have significant storage capacity. General Motors has been examining this possibility, for example. If a sufficiently large number of former EV batteries could be hooked up to the power grid, they could provide storage capacity for intermittent renewable energy sources.

Summary

To sum up, there are several types of renewable energy which can provide baseload power. Additionally, intermittent renewable energy can replace dirty energy sources like coal, although it currently requires a backup source such as natural gas which must be factored into the cost of intermittent sources. It will be over a decade before we can produce sufficient intermittent renewable energy to require high levels of storage, and there are several promising energy storage technologies. One study found that the UK power grid could accommodate approximately 10-20% of energy from intermittent renewable sources without a "significant issue" (Carbon Trust and DTI 2003). By the time renewable energy sources begin to displace a significant part of hydrocarbon generation, there may even be new storage technologies coming into play. The US Department of Energy has made large-scale energy storage one if its research priorities, recently awarding $24.7 million in research grants for Grid-Scale Rampable Intermittent Dispatchable Storage.

Comments

Peter Lang - Even on a quick read, the critiques do have some serious points. The ZCA proposal seems to grossly underestimate power demands (it will take quite some time and regulatory/pricing impetus to change heating/cooling methods), transportation energy needs, and quite possibly the build costs of the solar plants. The ZCA schedule is completely unreasonable, but that's not as much of a cost issue. I found the wind comments a little thinner - there's certainly a decent amount of 1.4-1.5MW generator costing available for consideration - but still a ZCA underestimate.

On the other hand, having looked at references such as Czisch (have you read this?), studying power availability using a large catchment basin, I think the wind availability numbers are really low. Not enough to overcome the optimism of the ZCA proposal, but still an underestimate.

As Bern noted, renewables do appear to be able to supply baseline power, albeit at what may be a higher cost. Of course, business as usual will have an extremely high cost too, just not in terms of energy...

If we ignore cost, I guess anything is "possible". But I doubt you could get more than about 1 to 5% firm power if you had wind farms spread all over Australia. The problem is that the wind just doesn't blow much in the places where wind farms are not being built. Furthermore, the cot of transmission alone would be many time higher than the cost of simply using the unprintable technology. It is just plain silly.

Regarding cost benefit of emissions reductions, the externality costs per MWh are included in the ExternE link I provided up thread. Numbers like $1,240 trillion are meaningless and probably come from a 'biased' researcher anyway.

I wonder if this estimate of cost benefit may not be more realistic:
http://johnhumphreys.com.au/2010/06/05/benefit-cost-analysis-for-the-ets/

What it really boils down to is that we should aim to cut emissions in the least cost way. If we keep hammering renewables and being anti-(unprintable), the vast majority of middle people are going to question the veracity of everything being advocated. Being economically irrational about how to cut emissions leads to questions about how rational and objective is the rest of the stuff being advocated by the groups with the same leanings. One doubt leads to another.

Peter Lang: "One problem is that many people have very little understanding of economics, costs, financing. It is impossible to have a rational discussion with people who want to talk about their beliefs and hopes but cannot or will not consider the cost of what they advocate."

This is very true. But either side can make this case - I would argue the renewable folks have the better case. I presented DOE/EIA data that showed wind, coal and gas all between US$53 and US$55/unit, the unmentionable at $60/unit and solar PV at $100/unit (best current case). CSP was not in that particular analysis, but usually weighs in roughly equal to wind.

We also have a "Moore's law" type phenomena where the more PV and CSP you do, the cheaper it gets (there will be limits to this).

We also have the fact that grid storage remains unexplored. Pilot projects have already been successful (as opposed to "clean coal" - which doesn't exist anywhere, for any amount of money, on planet earth).

Do you bet on the known technology with huge negatives (as we spend the weekend contemplating a rehash of the Korean war, only this time with nuclear weapons)?

Or do we look ahead to different, better technology?

I think the short term answer is you have to do both (ANYTHING to get us off of coal!) - but this rational person is putting his long terms bets on technology that improves over time.

Or maybe you would be willing to give me a penny today, and then double it tomorrow, repeat each day for one year? How about for one month? (a month would only be 5.3 MILLION dollars!).

The power of compound efficiency increases/cost reductions swings this one way in favor of renewables.

And the real world experience of PV, CSP and wind prove this is no pie-in-the-sky, but our best possible future (OK, with a helping of the unmentionable power as well).

More's Law does not apply. These are very high cost systems with long life times and so turn over and learning takes decades.

The costs you quoted for energy for wind and unprintable are not comparable. Not printable is baseload and dispatchable (meaning it can be called up any time as needed by the energy market operator). That is not the case for wind. Here is a rough comparison on an equal basis:
http://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/#comment-86108

Grid storage is not unexplored. It is simply totally un economic. The link above covers this too.

Placing a link between unprintable electricity generation technology and weapons is a furphy. Sorry. Waste of time even discussing it. Go to BraveNewClimate if you want to discuss that.

"I think the short term answer is you have to do both (ANYTHING to get us off of coal!) - but this rational person is putting his long terms bets on technology that improves over time."

Why would you bet on something that has low energy density (much lower than fossil fuels) and is not viable now and never likely to be? Why not bet on the technology that has 20,000 time higher energy density, is proven, and has been proven for 50 odd years?

Why delay any longer. Saying "I am prepared to accept unprintable will have a role but I want to put my efforts into renewables" is in reality just a way to continue to block unprintable. This is what has been happening for the past 40 years.

When I see this sort of argument, I believe the people pushing it, and pushing CAGW, are not serious about CAGW. They are more interested in pushing their beliefs.

You talk about doubling. Have you thought of applying the same logic to unprintable. For 40 years development has been blocked in the western democracies. We are still using the technology that uses only 1% of the available energy in the fuel.

Consider why you really prefer renewables. Is it rational or emotional? I know the answer, but can you recognise it?

00

Moderator Response: [Daniel Bailey] For posterity, please define what it is you mean by CAGW. Thanks!

"So far, it seems to me that renewable technologies are more expensive to implement, but I don't know if the operating costs always have to be that high. I think we need quite a lot of operation data for full-scale systems to make safe judgments."

I agree - there is this thing called "learning curve" and "experience curve" which applies to may products in modern (and old) world. Attributed to it is the price experience curve. This is valid for such different things as wind turbines, displays technology, transistors and many more. All of these have generated steady and predictable declines in the "price expereince curve" (PEC) and a "learning factor". The basic outcome for all of this is: with doubled production of a good (like a display, a turbine, or solar installation or other mass products), you get a predictable price decrease of X% - this X depends on the technology you investigate for. For solar modules for example, it is around 20%. Meaning: If world production of modules go from 9 GWp to 18 Gwp, you get 20% lower prices simply due to learning effects in production of this product.

I think, renewables as a whole are just at the beginning of this learning curve, so it is to early to judge what the experience factor truly is. For mature technologies like combustion engines, coal plants and such, the factor is much much lower due to the fact they went down all the way of the learning curve already. At a certain point, the curve deflects and gets rather flat.

Ultimately, the decline for the renewable cost curves should prove to be quite significant and therefore enable increased and widespread adoption of renewale technology for a variety of applications.

"Why would you bet on something that has low energy density (much lower than fossil fuels) and is not viable now and never likely to be? Why not bet on the technology that has 20,000 time higher energy density, is proven, and has been proven for 50 odd years?"

Energy density (per kg) does only matter if you want to transport something. It is not something relevant for decentralized, static energy production like what we talk about here. Look in the real world: nature showed us how with a conversion efficiency of only 1-3% (photosynthesis) all the energy wich finally ended up in coal, oil etc and even today in biomass (wood - which you burn), wind, water, sunlight was and is produced. So please dont explain that high energy density is a must for our energy production. It is a must for centralized power generation, that is true - but not for economic power generation per se.

I personally think that fossile and even nuclear energy production is extremly inefficient methods compared to renewable - you have to look at the efficiency in terms of usable (output) energy versus used (input) energy, not only at your power plant efficienc versus (e.g.) PV or wind efficiency: lets take coal - your cooking oven needs to boil 1 l of water, ok? Per thermal energy of water (CH2O=4.187 kJ/(kg*K)), you need 0.097 kWh to achieve this. With a high 38% efficiency assumed for conversion of primary energy (coal) to end energy (electricity) and some losses (45% assumed) when actually boiling it, you need 0.46 kWh of primary energy. So finally 79% of your primary energy input is gone somewhere°, only 21% of it is used. This is because all used power plants today are basically a carnot-process, wasting roughly 2/3 of the energy to start with. If you want to achieve this with renewble, the primary energy input is 0.175kWh to get the 0.97 kWh in the water - so with same losses assumed (45%) to actually boil the water, you have used 55% of the primar energy harvested. Its 55% versus 21%. There is no trick in this calculation, it is just looking at the overall cycle. I have not even talked about the 156 g CO2 generated by the coal plant or the effort to actually get it out of the mine or transport it...gas looks a bit better (31% efficiency). For nuclear i have not calculated but the ~2/3 loss of your primary energy loss will be the efficiency killer as well.

° if you want to use the heat from the coal plant in a CHP configuration, the situation for the totally used energy goes up in general, but you can again compare it to a combination of renewable sources producing heat and electricity. And I am not aware that any nuclear CHP plant is operating or even thought of.

PS: by the way, the denominator in your term ("density") is important (energy per what exactly?) - i can easily calculate an energy density - lets say - for silicon (in PV) which will blow your mind. But again: it is not relevant, it is just pulling wool over other people's eyes.

00

Moderator Response: [Daniel Bailey] Please, everyone: nuclear is off-topic on this thread. If you wish to discuss nuclear, please go to the What-should-we-do-about-climate-change thread I linked above. Thank you!

"If world production of modules go from 9 GWp to 18 Gwp, you get 20% lower prices simply due to learning effects in production of this product."

I should have been more accurate: it is not the world production, but the accumulated production of the good we talk of. The 9 and 18 were just arbirtrary numbers. Accumulated solar power is around 22 GWp produced until end of 2009 [1] while production rate in 2009 was around 12.3 GWp/year [2]. In that case, you'd get around 20% price decrease in less then 2 years.

Found an comprehensive overview on various price experience curves [3].

One reason energy density is very significant is the quantity of materials you need per unit of electricity generated. Where materials include concrete, steel, glass, plastic etc etc AND land. There is a very real correlation between environmental damage and quantity of materials. It is also why Moore's law is quite irrelevant - the miniaturization that underlies Moore's law is not pertinent to electricity generation from sources of low energy density. The land requirements of hydro and CSP are very damaging to ecosystems.

That is generally a valid point. For PV, i think one can use existing structures like roofs, so a lack of land or the need for land in that case i dont see. There are large installations as well on land which was of agricultural use before and this is recognized and countered. Also, land used with PV can (and is) be used as pasture for example. Regarding material, i think the cost and the life cycle assesments account for that already - and those numbers look good. For wind, the footprint is quite small, for materials the same argument as for PV holds. Regarding hydro, yes: land requirements are large for dams. CSP requires large amount of land but what kind of damage is exerted in the desert of Nevada or Spain?

On the other hand it sounds a bit like pretending: shall we really compare the impact on ecosystems of coal, oil or uranium exploration? The whole point of letting rest the fossile in peace is actually the impact on our ecosystem, right?

I'm unable to take anything Peter Lang says seriously I'm afraid, as the last time he turned up on this site, and was asked perfectly reasonable questions, he asserted that "this discussion is pointless" and disappeared. So I get the strong impression that there's an ideologically driven agenda here which when challenged results in logically flawed asserstions which are not proper arguments.

As always I'm happy to be corrected, but am still awaiting an answer to the question that I posed prior to the post at the link above.

Talk about ideological - what is more ideological than anti-N and pro-renewables at any cost?

I can't take much of the pro-renewables at any cost, anti- N ideological stuff when the advocacy is devoid of costs.

I've pointed you to a number of links where you can compare costs on a comparable basis. If you are not prepared to try to get your head around this material then there is no point in continuing the discussion. You keep pulling out bits and pieces all of which are not on any sort of comparable basis.

Come back with sensible, justifiable costings for a system that can produce the power demanded by modern society, and once you do you will understand why non-hydro renewables cannot do the job. And just before someone jumps in and says we are not concerned about cost I'll just add that renewables cannot do the job at any cost and are unlikely to ever be able to. But don't believe me, read the links I and Quokka hjave proivided today on the previous and this page. Over to you.

@Peter Lang: "Talk about ideological - what is more ideological than anti-N and pro-renewables at any cost?"

Peter, I think one of the reasons people here are reacting negatively to you Nuclear sales pitch is that, according to you, anyone who's not 100% behind Nuclear as the *only* solution is anti-nuclear. That is propagandist rhetoric at its ugliest.

It seems to me you would have much more success by advocating for nuclear alongside renewables. It may go against your ideals/mission, but which is best: sticking to your guns and losing, or making compromises and achieving partial success? Think about it.

"I'll just add that renewables cannot do the job at any cost and are unlikely to ever be able to."

This is other examples of why we can't take you seriously. Renewables are already providing significant amounts of power to the grid, and their large-scale deployment has barely begun. We're not even talking about technologies that might be feasible 20-30 years from now, such as Orbital Solar.

When you speak in such absolutist terms you make it clear this isn't a rational argument on your part, but a sales pitch that exaggerates the benefits of nuclear and the drawbacks of renewables.

@moderator: so sorry, I only now saw your requests (that's what happens when you go through "Recent Comments" instead of the actual threads...). I'll refrain from pushing the subject further here. Anyway, I've pretty much said everything I needed to say about Peter's aggressive sales pitch. I can't stand his not-so-veiled insults towards those who *dare* think renewables also have a place in the future energy mix.

As for their links, at this point it should be considered blogspam for Brave New Climate. When pretty much all of one's references come from a couple of web sites, it's usually a sign you're pushing some sort of agenda...

With all due respect to the great moderators here, I don't think a conversation regarding baseload power can be carried on without also discussing nuclear. It's a little like having one hand tied behind your back.

Peter @ 187 said, "They are not viable and probably never can be (at more than about 10% of the total generation)."

Did you miss the part where Steven Chu just stated that China is going to be 20% renewables by 2020?

The issue is "can baseload power come from renewables". The nuclear issue is separate from "can baseload come from renewables". Nuclear proponents have already hijacked several threads with their claims. Everyone agrees that nuclear can generate baseload energy if it can overcome its other problems. I am tired of the unsupported claims from nuclear proponents, see the linked thread. I have seen their claims more than once and do not need to see them repeated again here. I am agnostic about how much nuclear will end up being best, but it is tiring to have these wild claims repeated again and again.

I've asked you questions about things like synergisic effects, distributed generation, efficiency gains in the past, but you have not answered any of these questions. They're important issues which need to be considered when assessing electricity generation resources, but you don't seem to want to do so.

I haven't actually expressed any opinion on nuclear energy, so attacking my position as ideologically driven kneejerk anti-nuclear seems a bit of a stretch. However, from the fact that you haven't answered my perfectly reasonable questions, I can only assume that you won't because you have something to hide.

"Did you miss the part where Steven Chu just stated that China is going to be 20% renewables by 2020?"

Most of China's renewables are hydro.

I stated in some posts, and obviusly need to say it in every post, that I am referring to non-hydro renewables when I say renewables cannot provide baseload generation. I should also say that biomass and geothermal, in volcanic areas but not Australia, can provide baseload generation but in insignificantly small quantities.

The thread is about baseload. So the comment about China targeting 20% renewables is off topic.

Likewise, I am tired of the unsupported claims about non-hydro renewables being able to provide baseload power.

If non-hydro renewables can provide baseload generation, in significant quantities, show me where it is being done. I am not interested in theoretical studies by the advocates who are being fed almost entirely by tax payers’ money. Show me actual output from solar thermal and wind generation that demonstrate they can provide baseload generation. I am looking for charts like Figure 6 and 7 here which shows the actual output from a solar PV station at 30 minute intervals for two years. Note that the capacity factor on the worst days in winter is 0.75%. Some baseload!

So, please, for a start, show me two years of output from a solar thermal station with capacity factor around 85% and availability over 90%.

If you are going to argue that if you throw enough renewable technologies into the mix, then provide the costs. I’ll advise that you can add as many technologies as you like, you will still not have reliable power and the capital cost is the sum of all the technologies – that is orders of magnitude more costly than with fossil fuel and baseload generators.

You link didn't work. Can you provide a link showing how much of Australia's electricity is supplied by geothermal?

Since you probably wont, I'll answer the question for other readers. The answer is nil!

Furthermore, the hot dry/fractured rock type of geoothermal Australia is trying to develop has never been successful anywhere in the world despite almost 40 years of attempts.

Sure, we will get a little from demonstration plants in time, at huge cost to the tax payer, but it is insignificant. It is another massive waste of time, effort and a diversion of resources from solutions that have proved they can actually cut emissions significantly - in fact, theese solutions could cut emissions from electricity generation by nearly 100% in about 30 years, and do so in an economically rational way.

Peter... I don't believe Dr. Chu is talking about hydro or nuclear. I think he's only talking about wind and solar. Here is what I find: "In 2009, the rumored energy targets for China for 2020 were 300 GW Hydro, 75GW nuclear, 150GW from renewable if targets are reached. 46% of power would be from non-coal sources if natural gas usage is increased as projected." Link.

So, China is looking at 46% carbon-free electricity by 2020. So, I still hold your statement that anything over 10% renewables (wind and solar) is not feasible to be inaccurate.

If you will notice as well, China is putting in twice as much wind/solar as they are nuclear. Why would that be? It's certainly not because of protesters or onerous regulation.

Could it be that wind and solar have other big advantages? Exportable technologies. Improving efficiencies. Low hazards (failures). No hazardous materials.

"Most of China's renewables are hydro. [...]So the comment about China targeting 20% renewables is off topic."

The argument from Chu was probably more referring to something like the Martinot report [1]. So for 2020, the goal is 500 GWp renewable energy in China of which 200 GWp are non-hydro. I am reluctant to agree to your point that that qualifies to be "off-topic"when we talk about baseload.

You repeatedly state "[...] renewables cannot provide baseload generation" but i actually have the impression your argument is more about "If we ignore cost, I guess anything is "possible"." as you said in #202. I strongly propose we distinguish between those two: a couple of posters (including me) linked studies which show that technically, renewables can provide baseload power as a reliable power source to the energy mix. Regarding cost of these renewable baseload solutons I admit that i have no data regarding the cost but my guess is that they are higher than established solutions. However, this does not quaify for not being considered at all. The question then is: are all externalized costs accounted for when talking about cost of established solutions of baseload? And second: how fast can cost for renewable baseload power decrease? Third: is the society willing to accept the (lets say) "activtion cost" for this change to happen? Of course the final solution must be an economicaly viable under given boundary conditions (which might change by the way: politically and economically). I am not questioning the ability of society to bear it, but the willingness is a different thing. How could something like the bold race to the moon actually work out if you look at economics only?

#225 "adelady, You link didn't work." copy it manually and remove the last slash "\", then it works fine.

Awareness about the cost of renewables is spreading in Australia. Here are some recent examples:

1. "The Great Wind Rush" An excellent article in the 'Weekend Australian' about wind energy (and reference to the emission avoidance costs from my 2009 paper):
http://www.theaustralian.com.au/national-affairs/the-great-wind-rush/story-fn59niix-1225961297137

2. "Emission Reductions are not Blowin' in the Wind" - Another excellent article in Monday’s 'Australian' comparing the costs of low emissions generation technologies and dismissing wind and solar. This is a good article ands well worth reading (unfortunately the chart is not shown in the article)
http://www.theaustralian.com.au/national-affairs/emission-reductions-are-not-blowin-in-the-wind/story-fn59niix-1225962376534
You can see the chart here:
http://bravenewclimate.com/2010/11/28/nuclear-is-the-least-cost-low-carbon-baseload-power-source/

4. About three weeks ago, the NSW state government cut its feed in tariff for solar PV from 60c/kWh to 20c/kWh

5. The Australian Capital Territory (ACT) Government (A Labor-Green alliance), about two weeks ago, admitted its solar power program will increase the cost of electricity for users by about 25%. This has come as a shock and wake up call to the ACT residents (the greenest of all Australian State and Territory governments)

6. Yesterday the federal government cut its subsidies to the up front costs of solar panels from $6300 to $5000 per 1.5kW. It also announced the subsidies would be cut further each year and would be phased out a year earlier than previously planned. They also announced that cutting the subsidy from $6300 to $5000 would save the average householder $12 per year. So the Federal subsidy alone costs the average householder about $60 per year. The Feed in tariffs cost far more.

To put this in perspective, solar power generates about 0.1% of Australia’s electricity. Imagine what the subsidies would be if solar generated 10%, 20% or 50% of our electricity. Playing with numbers: 50% / 0.1% x ($60 + $225) pa = $142,500 pa per household subsidy.

Sure, you can pick at details about the numbers, but try to understand the scale of just how ludicrous is what we’ve been doing trying to promote solar and wind power.

1. Hydro will almost always have negative impact on landscape, but used in conjunction with solar/wind/biomass, with pumping, it can be rather non-invasive, considered its effect. Huge dams and small heights is something entirely different, and not distinguishing the different forms for utilization seems rather unserious to me.

2. It is rather incredible for me to have discussions about wind power without any reference to possible optimizations of stable output whatsoever. A system-wide optimization will almost always lead to very different design from local optimizations (for example operators maximizing their total production, with small or no regard to total supply situation, and subject to existing grid/transmission constraints). And the whole transmission system may have to be changed a lot. Which may require huge initial investments, but total costs over system lifetime are not necessarily very high.

3. It is impossible to discuss future energy systems on the basis of simple system changes, like phasing in PV, "everything else being equal". Even with no introduction of renewables at all, everything else will _not_ be equal over the course of some decades, which is the actual planning horizon for energy systems. I have to repeat it: "Baseload" is _not_ a well defined quantity, and with sufficiently strong incentives, renewables will _per definition_ be able to cover baseload. (As they have done in human history until fossil fuels came into widespread use.)

"200 GWp are non-hydro. I am reluctant to agree to your point that that qualifies to be "off-topic" when we talk about baseload."

Please explain how 200GWp power has anything to do with baseload power. Do you understand what baseload means? I think you don't. Can I urge you (and others) to read "The Case for Baseload" to assist you to understand what baseload means in the electricity industry (as opposed to the way renewable energy advocates are trying to re define it)

You quote me not completely: my point was that of 500 GWp renewable (which is 30% of the estimated need for China in 2020 if you read the report i linked to), 200GWp is non-hydro. So the 200 GWp is already over your artificial 10% threshold you are willing to neglect. I say the 200 GWp is large enough in order that baseload-ability has to be considered.

Also, I am looking forward to the rest of my points in #207 and not only the first 5 lines.

Peter... And if you watch the talk given by Dr. Chu he uses a story from Australia to illustrate his point. Chu toured a modern automated factory in China producing some of the most highly efficient solar panels in the world. The technology came from an Australian who could not get anything accomplished at home but found enthusiastic interest in China.

The factory producing these panels is not in China because of labor rates. It's an almost completely automated factory. It could be located anywhere. Now China is selling these panels to the rest of the world because the guy's own country couldn't see fit to invest.

You know, it's the people who sit around compiling reasons that things can't be done who ultimately never get anything done. The people who find a way to do it are the leaders of the world.

To get some perspective on the amount of land that would need to be innundated to allow solar to provide all our baseload power (a limit condition to help appreciate the scale of the problem), and the cost, I'd urge you to look at "Solar Power Realities".

The conclusions state:

"Solar power is uneconomic.

The capital cost of solar power would be 25 times more than power to provide the NEM’s demand.

The minimum power output, not the peak or average, is the main factor governing solar power’s economic viability.

The least cost solar option would emit 20 times more CO2 (over the full life cycle) and use at least 400 times more land area compared with .

Government mandates and subsidies hide the true cost of renewable energy."

To power the Australian National Electricity Market with solar PV and pumped hydro would require hydro dams that innundate 8,000 km2 of land area. However, we can't get approval to build any new dams of any size. They are opposed by you know who.

As I posted you before in #161, the german "Kombikraftwerk" was a study, were existing, real data from existing, real renewable PV, Wind, hydro (storage) and biomass power generators were taken over two consecutive years. Those real generation data were used to virtually combine those 36 power distributed generation sources and look at the combined output (resolution 1 h). In particular wind and PV very often complement each other (wind: strong in morning/evening, PV: strong at noon). Anyway, the outcome was that this kind of "virtual" power plant can fulfill all the requirements of baseload power. Its called "virtual" not because it is only a simulation but since the distributed sites will always be distributed and only connected virtually as a single plant to a control room which is tied to the rest of the grid. You can think of several of these virtual plants in one grid. Heck, in Germany there was > 15% renewable share of electricity production already in 2009 - and in 2020 the estimate is somewhere > 40%.

Peter Lang - I'll ask again, have you read Czisch and his discussion of minimum continuous power available when the system as a whole (rather than individual sites) is considered? You've been pointed to this article on European renewable power generation several times, but have not (as far as I've seen) commented on it.

The link you provided is a 30MB pdf by Geoscience Australia. I didn't download it but I am familiar with the argument. It runs something like this: "there are very large quantities of heat at depth and in some places they are closer to the surface than others".

That is all true. Just as there is limitless heat in the Sun. The problem with both geothermal and solar is turning that enormous amount of heat into electricity. In both cases the heat is diffuse, low energy density, and difficult to extract.

Peter Lang - Looking at your "Solar Power Realities" article, I see no mention of multiple sites. You appear to be taking the worst case scenario (a single site), and applying those production numbers to a system as a whole.

That's quite simply not realistic. Any reasonable renewable power plan (whether supplementary or baseline) will include multiple sites chosen for low correlation (negative, preferably), a mix of solar and wind, etc. That hugely lowers the power storage and backup turbine requirements, albeit with an increase in transmission costs.

A true comparison should include multiple siting in your calculations.

I forgot to mention the Andasol-power plant in Spain - Andasol 1 and 2 are already working and in operation, Andasol 3 is under construction since Sep 2009. Andasol is solar thermal only and has a huge storage tank (molten salt). Andasol can run continuously since the tank has enough energy to run for 8 consecutive hours over night. Each plant provides gross electricity output of 50 MWe. I think Australia might have some good places for that, too.

Quoting from the abstract: "Using locally mass-produced wind turbines there are good prospects that wind power would be cost-competitive with coal power, on a lifecycle cost basis, while providing substantial net environmental benefits."

It does not provide basload power and is hugely expensive (about 5 times the cost of (unprintable).

By the way 50MW peak power is about 30% of the power of an average car - but only available in the day time!! Get the message?

We'd need 1000 of these monsters to provide our pour during the day and a few hours at tnight and still need just as many reliable fossil fuel or (unprintable) power stations to provide the power during the night. They wouldn't replace any fossil fuel plants. Get the message yet?

Peter Lang - I think your accusation of "misinformation" is both highly insulting and contrary to the comments policy on this site.

I do not see an "Addendum" in your "Solar Realities" linked article, nor any reference to such in this thread. What I do see is a single-site power estimate (solar only), no consideration of an integrated grid, wind power (which would cover a considerable portion of the lower nighttime demands), multiple siting to minimize single site low periods, etc. Without consideration of these factors your "Realities" article is quite unrealistic.

I have not discussed costs because I do not have the information - I will clearly admit that. What I have been attempting to discuss for quite some time is the technical possibility of baseload power using renewables.

You have not proven your technical point with that article in any fashion.

don't type so quickly :) I get that you asked for examples, they were given. Are they cost effective today? Are the sufficient today? 2 x no. Was the first coal plant cost effective? sufficient? Same for nuclear or any new thing. Should we therefor abandon them - No. My 2 cent. And i dislike your agressive, unpolite tone.

And again, I have to ask... IF wind/solar can not possibly be economically feasible and IF nuclear is the obvious answer (as Peter claims) why would China be planning to install double the GW of power in wind over nuclear by 2020?

China could very easily take the same route as France and go all out for nuclear. They aren't. Why?

You did not provide the information I asked for. Pointing to one or more of the thousands of studies by renewable energy advocates which say that there are 'prospects' for renewables is simply trying to distract from revealing or accepting the truth of the matter. I've read plenty of these studies.

You quoted this fro the abstract:
" "Using locally mass-produced wind turbines there are good prospects that wind power would be cost-competitive with coal power,"

That should be enough to show you they are talking about "prospects" (i.e. pure advocacy for a belief, a hope, a wish and a prayer) and there is no mention that they can provide baseload. Clearly, you still do not understand what baseload means. If you want to uead the link I provided. If you don't want to understand, I cannot be bothered discussing it with you any more.

"By the way 50MW peak power is about 30% of the power of an average car - but only available in the day time!! Get the message?"

This is all wrong, sorry. You seem to have not read the linked article at all: it is not "peak" power. The heat is collected and converted to steam, then electricity. This is done continuously - the excess heat is stored in the molten salt tank - which seamlessly can take over in the evening hours or when clouds are there (You can easily think of a larger tank by the way). The tank provides continuously power for roughly 8 h.

Peter @ 248... You're simply arguing for inaction on the basis that it hasn't happened yet.

Look at your statements. You are using future tense in both cases. The abstract says, "there are good prospects..." But you are saying "cannot provide significant baseload generation." Both a reference to what can or can not be done.

The analogy would be someone arguing in 1963 that you can't put a man on the moon by saying, "Look! Show me one man that has ever walked on the moon!"